Mytilus (Falcimytilus) nasai Kobayashi and Ichikawa
1950a. Mytilus (Falcimytilus) nasai Kobayashi and Ichikawa, p. 208, pl. 1, figs. 2, 3.- 1950a. Mytilus (Falcimytilus) nasai var. nagaides Kobayashi and Ichikawa, p. 209, pl. 1, fig. 4.-1950a. Mytilus (Falcimytilus) nasai var. hirataides Kobayashi and Ichikawa, p. 209, pl. 1, fig. 5.-1954c. Mytilus (Falcimytilus) nasai Kobayashi and Ichikawa: Ichikawa, p. 46, pl. 1, fig. 11.-1954c. Mytilus (Falcimytilus) nasai var. nagaides Kobayashi and Ichikawa: Ichikawa, p. 47, pl. 1, fig. 10.-compare 1956. Mytilus (Falcimytilus) cf. nasai Kobayashi and Ichikawa: Nakazawa, p. 235, pl. 1, fig. 10.-1959b. Mytilus (Falcimytilus) nasai var. nagaides Kobayashi and Ichikawa: Tamura, p. 220, pl. 2, figs. 13, 14.-1959b. Mytilus (Falcimytilus) nasai var. hirataides Kobayashi and Ichikawa: Tamura, p. 221, pl. 2, fig. 15.
Type. —Holotype (UMUT MM5134) from Kashiwai, Sakawa, Kochi Pref. Holotype of Mytilus nasai var. nagaides (UMUT MM5135) from the same locality Holotype of Mytilus nasai vax. hirataides (UMUT MM5136) from Oowada Horiake, Sakawa, Kochi Pref.
Age and distribution. —Carnian. Kochigatani group (lower part) in Sakawa, Sakuradani and Sakamoto areas.

Mytilus (Falcimytilus ?) tenuiformis Kobayashi and Ichikawa
1950a. Mytilus tenuiformis Kobayashi and Ichikawa, p. 207, pl. 1, fig. 7.-1950a. Mytilus tenuiformis var. punctatus Kobayashi and Ichikawa, p. 208, pl. 1, fig. 8.-compare 1956. Mytilus cf. tenuiformis Kobayashi and Ichikawa: Nakazawa, p. 234, pl. 1, fig. 7.-compare 1956. Mytilus tenuiformis var. punctatus Kobayashi and Ichikawa: Nakazawa, p. 234, pl. 1, fig. 8.-compare 1956. Mytilus aff. tenuiformis var. punctatus Kobayashi and Ichikawa: Nakazawa, p. 234, pl. 1, fig. 9.
Type. —Holotype (UMUT MM5139) from Kashiwai, Sakawa, Kochi Pref. Holotype of Mytilus tenuiformis var. punctatus (UMUT MM5140) from Okunominetani, Sakawa, Kochi Pref.
Age and distribution. —Carman. Kochigatani group (lower part) in Sakawa area.

Mytilus (Falcimytilus) hirabarensis Tokuyama
1960c. Mytilus (Falcimytilus) hirabarensis Tokuyama, p. 210, pl. 13, fig. 9.
Type. —Holotype (UMUT MM4590) from Okubata, Mine, Yamaguchi Pref.
Age and distribution. —Carnian. Mine group (Hirabara formation) in Mine area.

Mytilus (Falcimytilus) heranirus Hayami
1958a. Mytilus (Falcimytilus) heranirus Hayami, p. 160, pl. 24, figs. 3, 4.-compare 1958a.
Mytilus (Falcimytilus) heranirus Hayami subsp.: Hayami, p. 160, pl. 24, fig. 5.
Type. —Holotype (UMUT MM2723) from Kuruma, Otari, Nagano Pref.
Age and distribution. —Pliensbachian (or thereabout). Kuruma group (Tsuchizawa formation) in Otari area.

Mytilus (Falcimytilus) stricapillatus Hayami
1958a. Mytilus (Falcimytilus) stricapillatus Hayami, p. 159, pl. 23, figs. 8-11.-1958a. Mytilus (Falcimytilus) stricapillatus Hayami subsp.: Hayami, p. 159, pl. 24, figs. 1, 2.
Type. —Holotype (UMUT MM2726) from Shinatani, Omi (Agero), Niigata Pref.
Age and distribution. —Pliensbachian-Toarchian. Kuruma group (Shinatani, Negoya and Tsuchizawa formations) in Omi, Asahi and Otari areas.

Mytilus punctus Ichikawa
1954b. Mytilus (?) punctus Ichikawa, p. 50, pl. 7, figs. 9-10.
Type. —Holotype (UMUT MM5424) from Arai, Hinode, Tokyo Pref.
Age and distribution. —Triassic (precisely unknown). Arai formation in Itsukaichi area.
Remarks. —The relationship between the following Mytilus chohi and the present species should be further studied, because they may be actually conspecific.

Mytilus chohi Ichikawa
1954b. Mytilus (?) chohi Ichikawa, p. 48, pl. 7, figs. 11, 12.
Type. —Holotype (UMUT MM5419) from "M-valley" near Iwai, Hinode, Tokyo Pref.
Age and distribution. —Triassic (precisely unknown). Arai formation in Itsukaichi area.

Lycettia sp. cf. L. lanceolata (Sowerby)
1958. Dreissensia cf. lanceolata (Sowerby): Amano and Furuzawa, p. 23, text-fig01s. 1, 2.
Age and distribution. —Albian (?)-Cenomanian. Gosyonoura group in Shishijima island, and Middle Yezo group (Mikasa sandstone) in Ikushumbetsu area.

Arcomytilus dairensis Kobayashi and Hayami
1958a. Arcomytilus dairensis Kobayashi and Hayami, in Hayami, p. 158, pl. 23, figs, 5, 6.
Type. —Holotype (UMUT MM2734) from the River Daira, Asahi, Toyama Pref.
Age and distribution. —Pliensbachian or Toarcian. Kuruma group (Shinatani formation?) in Asahi area.

Arcomytilus laitmairensis (de Loriol)
1960b. Brachidontes (Arcomytilus) laitmairensis (de Loriol): Tamura, p. 277, pl. 32, figs. 3, 4.-1960d. Brachidontes (Arcomytilus) laitmairensis (de Loriol): Tamura, p. 232, pl. 2, fig. 7.
Age and distribution. —Upper Jurassic (especially Kimmeridgian). Soma group (Nakano-sawa formation) in Soma area, and Torinosu group in Sakawa area. This species was originally described from Alps and also reported from the Bathonian-Kimmeridgian of England, France, Somaliland and Cutch.

Brachidontes nankoi Ichikawa and Maeda
1958b. Brachidontes nankoi Ichikawa and Maeda, p. 95, pl. 6, fig. 1.
Type. —Holotype (OCU MM232) from Chikusa, Sumoto (Awaji), Hyogo Pref.
Age and distribution. —Campanian. Izumi group (Shichi shale) in Awaji island, Himenoura group in Amakusa islands, and Kuji group in Nodatamagawa area.

Limnoperna? sengokuensis Hase
1960. Limnoperna (?) sengokuensis Hase, p. 318, pl. 36, figs. 23-29.
Type. —Holotype (IGSH HA161) from Sengoku, Miyata, Fukuoka Pref.
Age and distribution. —Lower Cretaceous (precisely unknown). Kwanmon group (Sen-goku and Wakamiya formations) in Miyata and.Toyonishi areas.

Modiolus paronaiformis (Kobayashi and Ichikawa)
1950a. Volsella paronaiformis Kobayashi and Ichikawa, p. 210, pl. 1, fig. 1.-compare 1956. Volsella aff. paronaiformis Kobayashi and Ichikawa: Nakazawa, p. 236, pl. 1, figs. 16, 17.
Type. —Holotype (UMUT MM5133) from Umenokidani, Sakawa, Kochi Pref.
Age and distribution. —Carnian. Kochigatani group (lower part) in Sakawa area.

Modiolus nagatoensis Tokuyama
1960a. Modiolus nagatoensis Tokuyama, p. 36, pl. 4, fig. 14.
Type. —Holotype (UMUT MM4561) from Higaeribara, Mine, Yamaguchi Pref.
Age and distribution. —Carnian (or lower Norian). Mine group (Aso formation) in Mine area.
Remarks. —This species seems to be closely related, if not identical, to Modiolus paronai-formis.

Modiolus okubatensis Tokuyama
1960c. Modiolus okubatensis Tokuyama, p. 210, pl. 13, figs. 6-8.
Type. —Holotype (UMUT MM4587) from Hirabarazaka, Mine, Yamaguchi Pref.
Age and distribution. —Carnian. Mine group (Hirabara formation) in Mine area.

Modiolus bakevelloides (Hayami) [Pl. 1, Fig. 12]
1958a. Volsella bakevelloides Hayami, p. 156, pl. 23, figs. 1-3.-1958d. Modiolus bakevelloides (Hayami): Hayami, p1. 28, fig. 4.
Type. —Holotype (UMUT MM2719) from Niranohama, Utatsu, Miyagi Pref.
Age and distribution. —Hettangian. Shizukawa group (Niranohama formation) in Shizukawa area.

Explanation of Plate 1 Fig. 1. Trigonucula sakawana Ichikawa: type-species of genus Trigonucula. Holotype (UMUT MM 5242), rubber cast from left external mould, ×2. Loc. Umenokidani, Sakawa (Carnian, Kochigatani group). Fig. 2. Solemya suprajurensis Hayami. Holotype (UMUT MM3138), internal mould of right valve, ×1. Loc. Mitarai, Makito (Callovian, Tetori group). Fig. 3, Parallelodon (Palaeocucullaea) monobensis Nakazawa: type-species of subgenus Palaeocucullaea. Rubber cast from left internal mould (UMUT MM4571), ×1. Loc. Hirabarazaka, Mine (Carnian, Mine group). Fig. 4. Parallelodon (Torinosucatella) kobayashii (Tamura): type-species of subgenus Torinosucatella. Rubber cast from left external mould (UMUT MM3207), ×1.5. Loc. Tatenosawa, Soma (Kimmeridgian, Soma group). Fig. 5. The same species. Left valve (UMUT MM3206), ×1.5. Loc. ditto. Fig. 6. Matsumotoa japonica Okada: type-species of genus Matsumotoa. Holotype (GK H6027), rubber cast from right internal mould, ×1. Loc. Tsuzumugi, Mifune (Cenomanian-Turonian, Mifune group). Fig. 7. The same species. Paratype (GK H6026), left valve, ×1.5. Loc. Kanayama, Masuki (Cenomanian-Turonian, Mifune group). Fig. 8. Glycymeris (Pseudoveletuceta) mifunensis Tashiro: type-species of subgenus Pseudoveletuceta. Holotype (KE 1774), rubber cast from right internal mould, ×1.5. Loc. Asanoyabu, Mifune (Cenomanian-Turonian, Mifune group). Fig. 9. Glycymeris (Hanaia) densilineata Nagao: type-species of subgenus Hanaia. Left valve (GK H6219), ×1.5. Loc. Haipe, Tanohata (Aptian, Miyako group). Fig. 10. The same species. Topotype (GK H6352), right valve, ×1.5. Loc. Hiraiga, Tanohata (Aptian, Miyako group). Fig. 11. Inoperna plicata (Sowerby). Right valve (UMUT MM3264), ×1. Loc. Yamashita, Soma (Kimmeridgian, Soma group). Fig. 12. Modiolus bakevelloides (Hayami). Holotype (UMUT MM2719), right valve, ×1. Loc. Niranohama, Shizukawa (Hettangian, Shizukawa group). Fig. 13. Pinna (Plesiopinna) airiniformis (Amano): type-species of subgenus Plesiopinna. Holotype (KU not registered), right valve, ×1. Loc. Shishijima (Albian?-Cenomanian, Gosyonoura group). Fig. 14. Pteria masatanii Tamura. Holotype (UMUT MM3236), left valve, ×1. Loc. Tatenosawa, Soma (Kimmeridgian, Soma group). Fig. 15. Pteroperna pauciradiata Tamura. Holotype (UMUT MM3246), left valve, ×1. Loc. Tatenosawa, Soma (Kimmeridgian, Soma group). Fig. 16. Somapteria koikensis Tamura: type-species of genus Somapteria. Holotype (UMUT MM3242), right valve, ×1.5. Loc. Koike, Soma (Kimmeridgian, Soma group).

Modiolus magatama Hayami
1959h. Modiolus magatama Hayami, p. 46, pl. 5, fig. 13.
Type. —Holotype (UMUT MM3366) from Higashinagano, Toyoda, Yamaguchi Pref.
Age and distribution. —Sinemurian. Toyoda group (Higashinagano formation) in Toyoda area.

Modiolus sp. cf. M. bipartitus Sowerby
1960b. Modiolus cf. bipartitus J. Sowerby: Tamura, p. 276, pl. 32, figs. 19, 20.
Age and distribution. —Kimmeridgian. Soma group (Nakanosawa formation) in Soma area.

Modiolus maedae Hayami
1959f. Modiolus maedae Hayami, p. 145, pl. 12, figs. 8-10.
Type. —Holotype (UMUT MM3145) from Mitarai, Shokawa, Gifu Pref.
Age and distribution. —Callovian. Tetori group (Mitarai formation) in Makito area.

Modiolus falcatus Amano
1957b. Modiolus falcatus Amano, p. 91, pl. 2, figs. 3-8.-1965a. Modiolus falcatus Amano: Hayami, p. 255, pl. 30, figs. 1, 2.
Type. —Holotype (UMUT KML0058) from Hagino, Kahoku, Kochi Pref.
Age and distribution. —Upper Neocomian-Aptian. Monobegawa group (Hagino forma-tion) in Monobegawa area, Arita formation in Yuasa area, and Miyako group (Hiraiga formation) in Tonohata area.

Modiolus sp. aff. M. subsimplex d'Orbigny
1965a. Modiolus sp. aff. M. subsimplex d'Orbigny: Hayami, p. 256, pl. 30, fig. 3.
Age and distribution. —Upper Neocomian-Aptian. Arita formation in Yuasa area.

Modiolus ezoensis Yabe and Nagao
1928. Modiolus esoensis Yabe and Nagao, p. 89, pl. 17, fig. 11.
Type. —Holotype by monotypy (IGPS no. 22627) from Washinosawa, Horomui, Ishi-kari Prov., Hokkaido.
Age and distribution. —Cenomanian-Turonian(?). Middle Yezo group (?) in Horomui area.

Modiolus shimonadensis Ichikawa and Maeda
1958b. Modiolus shimonadensis Ichikawa and Maeda, p. 93, pl. 6, fig. 2.
Type. —Holotype (OCU MM231) from Haraikawa, Nandan (Awaji), Hyogo Pref.
Age and distribution. —Maestrichtian. Izumi group (Shimonada siltstone) in Awaji island.

Inoperna plicata (Sowerby) [Pl. 1, Fig. 11]
1960b. Modiolus (Inoperna) plicatus ]. Sowerby: Tamura, p. 276, pl. 32, figs. 5-8.
Age and distribution. —Kimmeridgian. Soma group (Nakanosawa formation) in Soma area. This species has been reported from the Middle and Upper Jurassic of various areas in European and Tethyan regions.

Amygdalum ishidoense (Yabe and Nagao)
1926. Modiola (?) ishidoensis Yabe and Nagao, in Yabe, Nagao and Shimizu, p. 63, pl. 13, fig. 42.-1934. Gervillia? sp.: Nagao, p. 201, pl. 24, fig. 2.-1965a. Amygdalum ishidoense (Yabe and Nagao): Hayami, p. 257, pl. 30, figs. 4-10.-compare 1965. Amygdalum sp. aff. A. ishidoense (Yabe and Nagao): Matsumoto, Hayami and Hashimoto, p. 9, pl. 1, fig. 12.
Type. —Holotype by monotypy (IGPS no. 8750) from Ishido, Ohinata, Nagano Pref.
Age and distribution. —Upper Neocomian-Aptian. Ishido formation in Sanchu area, and Miyako group (Hiraiga formation) in Tanohata area.

Lecompteus sp. cf. L. guerangeri (d'Orbigny)
1965a. Lecompteus sp. cf. L. guerangeri (d'Orbigny): Hayami, p. 259, pl. 30, figs. 11, 12.
Age and distribution. —Aptian. Miyako group (Hiraiga formation) in Omoto area.

Crenella gyliakina Matsumoto
1938. Crenella gyliakina Matsumoto, p. 16, pl. 1, figs. 9-11.
Type. —Holotype (UMUT MM 7747) from Ikushumbetsu, Mikasa, Ishikari Prov., Hokkaido.
Age and distribution. —Cenomanian-Turonian. Middle Yezo group (Mikasa sandstone) in Ikushumbetsu area, and Gosyonoura group in Gosyonoura island.

Pinna (Pinna) muikadaniensis Nakazawa
1961. Pinna muikadaniensis Nakazawa, p. 267, pl. 13, figs, 14-17.
Type. —Syntype (UK JM10711-10714) from Muikadani, Oe, and Kamiochi, Fukuchiyama, Kyoto Pref.
Age and distribution. —Skytian. Yakuno group (Oro formation) in Maizuru zone.

Pinna (Pinna) sp.
1955. Pinna sp. cf. P. aff. lima Böhm in Reed: Nakazawa, p. 252, pl. 14, figs. 8-10.
Age and distribution. —Carman. Nabae group (N2 and N3 formation) and Heki formation in Maizuru zone.

Pinna (Pinna) sp. cf. P. (P.) mitis Philips
1960b. Pinna cf. mitis Philips: Tamura, p. 278, pl. 32, figs. 12-14.
Age and distribution. —Kimmeridgian. Soma group (Nakanosawa formation) in Soma area.

Pinna (Pinna) sp. aff. P. (P.) sandsfootensis Arkell
1959f. Pinna sp. ex gr. sandsfootensis Arkell: Hayami, p. 147, pl. 12, figs. 12, 13.
Age and distribution. —Callovian. Tetori group (Mitarai formation) in Makito area.

Pinna (Pinna) sp. cf. P. (P.) robinaldina d'Oribgny
1957b. Pinna sp.: Amano, p. 85, pl. 1, figs. 10-13.-1965a. Pinna sp. cf, P. robinaldina d'Orbigny: Hayami, p. 281, pl. 39, figs. 2, 3.-compare 1972. Pinna sp. cf. P. robinaldina d'Orbigny: Shikama and Suzuki, pl. 4, fig. 11.
Age and distribution. —Upper Neocomian-Aptian. Monobegawa group (Hagino forma-tion) in Monobegawa area, Ishido formation in Sanchu area, and Hinagu formation in Sakamoto area.

Pinna (Pinna) saitoi Nagao
1932a. Pinna aff. breveri Gabb: Nagao, p. 35, pl. 5, fig. 1.-1938. Pinna saitoi Nagao, p. 125, pl. 15, figs. 9, 10.
Type. —Lectotype here designated (Nagao, 1938, pl. 15, fig. 9. GMH no. 8230) from Ponhorokabetsu, Yubari, Ishikari Prov., Hokkaido.
Age and distribution. —Middle Yezo group (Mikasa sandstone) in Yubari area, and Upper Yezo group in Abeshinai area.

Pinna (Plesiopinna) atrmiformis (Amano) [Pl. 1, Fig. 13]
1956. Plesiopinna atriniformis Amano, p. 71, pl. 1, figs. 1-5.
Type. —Holotype (KU not registered) from Shishijima, Azuma, Kagoshima Pref.
Age and distribution. —Albian ( ?)-Cenomanian. Gosyonoura group in Shishijima island.

Atrina heiensis Hayami
1965a. Atrina heiensis Hayami, p. 283, pl. 40, fig. 7.
Type. —Holotype (GK H6262) from Raga, Tanohata, Iwate Pref.
Age and distribution. —Aptian (or lower Albian). Miyako group (Hiraiga formation) in Tanohata area.